| RefNo | Title | Date |
| PB/8/10/4 | Correspondence with scientific colleagues, with recollections and information on Evan James Williams's work and personality. | 1945-1946 |
| PB/9/1/101/10 | Royal Society correspondence | 1969 |
| PB/4/9/2/9 | 'Towed charge as A/U weapon' | 7 March 1945 |
| PB/3/1/3/4/3 | Correspondence with FG Major | 1954 |
| PB/1/33/1/6 | Nobel Prize | 1948 |
| IM/GA/WRS/9063 | McCrea, William Hunter | nd |
| PB/3/1/3/3/27 | Correspondence with WH McCrea following Blackett's 1947 paper on magnetism | August 1947 |
| HWT/33/13 | H W Thompson's personal correspondence as Foreign Secretary | July - September 1971 |
| PB/2/5/2/2 | Correspondence and notes by others | 1956-1957 |
| IM/GA/WS/4349 | McCrea, William Hunter | nd |
| EC/1952/13 | McCrea, Sir William Hunter: certificate of election to the Royal Society | |
| PB/8/75/2/3 | Correspondence re current developments in British Astronomy. | 1967 |
| PB/9/1/101/3 | Royal Society correspondence | 1960-1961 |
| TG/1/2/7 | Letter from Thomas Gold to Professor William Hunter McCrea, Royal Holloway College, Eaglefield Green, Surrey | 1 July 1964 |
| PB/1/33/2 | Correspondence concerning the Copley Medal of the Royal Society | 1956 |
| RR/50/53 | Referee's report by George Neville Watson, on a paper 'Boundary conditions for the wave equation' by William Hunter McCrea and R A Newing | 14 April 1933 |
| RR/75/234 | Referee's report by William Hunter McCrea, on a paper 'Orbits and rays in the gravitational field of a finite sphere according to the theory of A N Whitehead' by John Lighton Synge | [1951] |
| RR/75/231 | Letter from William Hunter McCrea, on a paper 'Orbits and rays in the gravitational field of a finite sphere according to the theory of A N Whitehead' by John Lighton Synge, to D C Martin, assistant secretary of the Royal Society | 17 September 1951 |
| RR/75/1 | Referee's report by Paul Adrien Maurice Dirac, on a paper 'Relativity theory and the creation of matter' by William Hunter McCrea | 18 January 1951 |
| RR/75/232 | Referee's report by William Hunter McCrea, on a paper 'Orbits and rays in the gravitational field of a finite sphere according to the theory of A N Whitehead' by John Lighton Synge | 17 September 1951 |
| RR/75/233 | Letter from William Hunter McCrea, on a paper 'Orbits and rays in the gravitational field of a finite sphere according to the theory of A N Whitehead' by John Lighton Synge, to D C Martin, assistant secretary of the Royal Society | 8 October 1951 |
| RR/75/235 | Letter from William Hunter McCrea, on a paper 'Orbits and rays in the gravitational field of a finite sphere according to the theory of A N Whitehead' by John Lighton Synge, to D C Martin, assistant secretary of the Royal Society | 14 November 1951 |
| RR/79/267 | Referee's report by William Hunter McCrea, on a paper 'Some instabilities of a completely ionised plasma' by Martin David Kruskal and Martin Schwarzschild | 26 November 1953 |